Wheat does not pop off in the dark

When the light level is too low, wheat doesnt pop off of the block when updated.

In previous versions of minecraft, when the light level was too low wheat would pop off when updated/

To replicate, make an entirely dark room then add a light source. Plant seeds and then turn off the light. In 1.6.4, when you destroyed a plant, the ones next to it would update. In the snapshots, it stays.